Understanding Neurotoxin-Related Seafood Poisoning: Risks and Symptoms

Contaminated Seafood Linked to Fatalities

Authorities in Vizhinjam, along with medical professionals, have raised concerns about seafood that may have caused the deaths of two individuals and hospitalized four others. This seafood is suspected to contain a potent marine neurotoxin, potentially tetrodotoxin (TTX). The affected family consumed the seafood from a local restaurant on February 16, with two members succumbing to the effects shortly after. While food poisoning typically leads to gastrointestinal issues, toxin-induced seafood illnesses can severely impact the nervous system and worsen rapidly without timely intervention. Health officials are investigating the possibility of naturally occurring marine toxins, which are resistant to standard cooking methods. Reports indicate that additional patrons from the same restaurant have also fallen ill, with authorities suspecting the presence of ciguatoxin in red snapper (Chempalli) sourced from the Tamil Nadu coast.

What is Neurotoxin-Related Seafood Poisoning?

Certain fish and shellfish can accumulate toxins produced by microscopic algae in the ocean, leading to neurotoxic food poisoning that affects the brain and nervous system rather than just the digestive tract. Common types of toxin-related seafood poisoning include:

• Ciguatera poisoning (from reef fish)
• Paralytic shellfish poisoning (PSP)
• Neurotoxic shellfish poisoning (NSP)
• Scombroid poisoning (from improperly stored fish)

Medical experts note that, unlike bacterial food poisoning caused by pathogens like Salmonella or E. coli, these toxins remain stable under heat, meaning cooking does not render the seafood safe.

Recognizing Symptoms of Neurotoxin-Related Seafood Poisoning

Symptoms of neurotoxin-related seafood poisoning often start with common food poisoning signs such as nausea, vomiting, and diarrhea. However, neurological symptoms can quickly follow, including:

• Tingling or numbness around the mouth
• Burning or “electric shock” sensations
• Muscle weakness
• Blurred or double vision
• Difficulty speaking or swallowing
• Dizziness
• Breathlessness

In severe instances, these toxins can disrupt nerve signaling, leading to respiratory distress or paralysis, which constitutes a medical emergency requiring immediate attention.

How Does Seafood Become Toxic?

The majority of seafood toxins are associated with harmful algal blooms, commonly referred to as “red tides.” During these occurrences, shellfish and certain fish can accumulate toxins without showing any signs of spoilage. The seafood may appear, smell, and taste normal. Additionally, improper refrigeration can cause toxin accumulation in fish such as tuna and mackerel, leading to histamine poisoning, which often mimics allergic reactions with symptoms like flushing, rashes, and palpitations.

Treatment and Recovery from Seafood Poisoning

While there is no specific antidote for most marine toxins, treatment generally focuses on:

• Supportive care
• Intravenous fluids
• Respiratory support if necessary
• Monitoring in severe cases

Most patients can recover with prompt medical intervention, but delays can lead to severe complications or even death.